1. Field of the Invention
The present invention relates to an electronic device, and more particularly, to an electronic device so designed that an external memory, which has various pieces of data and programs stored therein and contains a control circuit or the like, can detachably be installed in this device.
2. Description of the Related Art
In an electronic device, particularly, a portable electronic device, such as an electronic notebook designed to be capable of storing telephone number data, address data, schedule data, etc., an internal memory cannot have a large memory capacity, limited by the portability and cost of the device.
In this respect, electronic devices designed to permit detachable installation of an external memory thereto have been proposed. Among them is, for example, a type which allows an IC card, a ROM pack, CD (compact disk) or the like to be detachably attached to the electronic devices.
This type of an electronic device the permits detachable installation of an external memory thereto is so designed as to permit different data and programs of different purposes (dictionary, name cards management, etc.) to be stored in different external memories and allow a user to change the installed external memory according to the purpose.
In such a conventional electronic device, a memory retaining section for accommodating the external memory is formed in the body case of the device, and is to be generally covered with a cover after the external memory is retained in that memory retaining section.
To provide the space for the cover, the conventional electronic device that is demanded to be compact has a retaining section for an external memory formed in a free or unused area on the side, bottom or top of the body case.
In this conventional electronic device, with external memory retaining section formed on the side or hot tom of the body case, it is inevitable that a user should the position of the electronic device or turn the device upside down to install or detach an external memory. This work of installation and detachment of an external memory is troublesome and deteriorates the usability of such an electronic device.
If the external memory retaining section is formed on the top of the body case, however, it is inevitable to restrict the sizes of a key input section and a display section or other members, which are normally provided on the top of the body case. This design requires that keys be made smaller or the display section be designed smaller, which is not desirable in view of good operability and high visibility of information.
In the conventional electronic device, the external memory and the retaining section have a predetermined positional relationship such that the external memory cannot electrically be connected to the body case unless the external memory is placed in a predetermined state in the retaining section. This conventional structure necessitates that the user should check the positional relation every time when placing the external memory in the retaining section, taking time in replacing the external memory with another one.